The present invention relates to a sample analyzer for analyzing a clinical sample such as blood, urine or the like. The present invention also relates to a method for controlling such a sample analyzer.
A sample processing apparatus for aspirating a sample through an aspirating tube from a sample tube containing samples such as blood, urine or the like, and processing the sample is known.
If the sample processing apparatus is used for a long time, dirt may be accumulated in a fluid system such as aspiration tube, flow path, valve, reaction tube, and analyzing section. This may cause a lowering of the accuracy or cause operation failure. Thus the fluid system needs to be periodically washed for every predetermined time period or for every predetermined number of tests.
Japanese Laid-Open Patent Application No. 2003-254980 discloses a specimen analyzer featured in an automatic washing. The apparatus is capable of aspirating a washing fluid contained in a fluid tube through an aspirating section, and washing an interior fluid circuit. With such configuration, when a rack holding the washing fluid tube is set in the specimen analyzer, the set rack is transported. The washing fluid is automatically aspirated from the washing fluid tube and the fluid circuit is washed when the apparatus recognizes that the transported tube on the rack is washing fluid tube.
The washing of the fluid circuit using the washing fluid is carried out by filling the chamber used to prepare a measurement specimen, the detection unit, and the flow path for connecting the same with the washing fluid and leaving it untouched for a certain time, and thereby causing the dirt deposited inside the chamber and the flow path to be solved into the washing fluid. Therefore, a long time is required to perform a washing once. Accordingly, the sample cannot be measured for a long time once the washing is started. The washing using the washing fluid is thus preferably performed after all the measurements of the sample are finished.
However, some samples require to be subject to re-measurement after the initial measurement. The determination on whether or not re-measurement is necessary is not made immediately after the completion of initial measurement, that is, there is a time lag between the time when the initial measurement is finished and the time when the determination is completed.
Thus, there may be such a case where it is determined that a sample requires to be re-measured by a measurement apparatus, after that the measurement apparatus finished an aspiration of washing fluid from a washing fluid tube, In this case, the re-measurement of the sample needs to wait for a long time until the washing is finished.